標籤:下拉式清單 listview wifi
有些列表資訊需要手動去更新,此時比較常用的就是下拉重新整理列表,在這裡就使用下拉式清單來重新整理當前Wifi資訊
目錄結構
介面
關鍵代碼
下拉式清單類
package com.example.dropdownrefresh.ui;import java.text.SimpleDateFormat;import java.util.Date;import com.example.dropdownrefresh.R;import android.content.Context;import android.util.AttributeSet;import android.util.Log;import android.view.LayoutInflater;import android.view.MotionEvent;import android.view.View;import android.view.ViewGroup;import android.view.animation.LinearInterpolator;import android.view.animation.RotateAnimation;import android.widget.AbsListView;import android.widget.AbsListView.OnScrollListener;import android.widget.BaseAdapter;import android.widget.ImageView;import android.widget.LinearLayout;import android.widget.ListView;import android.widget.ProgressBar;import android.widget.TextView;/** * 下拉式清單類 * @author Administrator * */public class DropdownListView extends ListView implements OnScrollListener {private static final String TAG = "listview";private final static int RELEASE_To_REFRESH = 0;private final static int PULL_To_REFRESH = 1;private final static int REFRESHING = 2;private final static int DONE = 3;private final static int LOADING = 4;// 實際的padding的距離與介面上位移距離的比例private final static int RATIO = 3;private LayoutInflater inflater;private LinearLayout headView;private TextView tipsTextview;private TextView lastUpdatedTextView;private ImageView arrowImageView;private ProgressBar progressBar;private RotateAnimation animation;private RotateAnimation reverseAnimation;// 用於保證startY的值在一個完整的touch事件中只被記錄一次private boolean isRecored;private int headContentWidth;private int headContentHeight;private int startY;private int firstItemIndex;private int state;private boolean isBack;private OnRefreshListener refreshListener;private boolean isRefreshable;public DropdownListView(Context context) {super(context);// TODO Auto-generated constructor stubinit(context);}public DropdownListView(Context context, AttributeSet attrs) {super(context, attrs);init(context);}private void init(Context context) {setCacheColorHint(context.getResources().getColor(R.color.transparent));inflater = LayoutInflater.from(context);headView = (LinearLayout) inflater.inflate(R.layout.head, null);arrowImageView = (ImageView) headView.findViewById(R.id.head_arrowImageView);arrowImageView.setMinimumWidth(70);arrowImageView.setMinimumHeight(50);progressBar = (ProgressBar) headView.findViewById(R.id.head_progressBar);tipsTextview = (TextView) headView.findViewById(R.id.head_tipsTextView);lastUpdatedTextView = (TextView) headView.findViewById(R.id.head_lastUpdatedTextView);measureView(headView);headContentHeight = headView.getMeasuredHeight();headContentWidth = headView.getMeasuredWidth();headView.setPadding(0, -1 * headContentHeight, 0, 0);headView.invalidate();Log.v("size", "width:" + headContentWidth + " height:"+ headContentHeight);addHeaderView(headView, null, false);setOnScrollListener(this);animation = new RotateAnimation(0, -180,RotateAnimation.RELATIVE_TO_SELF, 0.5f,RotateAnimation.RELATIVE_TO_SELF, 0.5f);animation.setInterpolator(new LinearInterpolator());animation.setDuration(250);animation.setFillAfter(true);reverseAnimation = new RotateAnimation(-180, 0,RotateAnimation.RELATIVE_TO_SELF, 0.5f,RotateAnimation.RELATIVE_TO_SELF, 0.5f);reverseAnimation.setInterpolator(new LinearInterpolator());reverseAnimation.setDuration(200);reverseAnimation.setFillAfter(true);state = DONE;isRefreshable = false;}@Overridepublic void onScroll(AbsListView arg0, int firstVisiableItem, int arg2,int arg3) {// TODO Auto-generated method stubfirstItemIndex = firstVisiableItem;}@Overridepublic void onScrollStateChanged(AbsListView view, int scrollState) {// TODO Auto-generated method stub}public boolean onTouchEvent(MotionEvent event) {if (isRefreshable) {switch (event.getAction()) {case MotionEvent.ACTION_DOWN:if (firstItemIndex == 0 && !isRecored) {isRecored = true;startY = (int) event.getY();Log.v(TAG, "在down時候記錄當前位置‘");}break;case MotionEvent.ACTION_UP:if (state != REFRESHING && state != LOADING) {if (state == DONE) {// 什麼都不做}if (state == PULL_To_REFRESH) {state = DONE;changeHeaderViewByState();Log.v(TAG, "由下拉重新整理狀態,到done狀態");}if (state == RELEASE_To_REFRESH) {state = REFRESHING;changeHeaderViewByState();onRefresh();Log.v(TAG, "由鬆開重新整理狀態,到done狀態");}}isRecored = false;isBack = false;break;case MotionEvent.ACTION_MOVE:int tempY = (int) event.getY();if (!isRecored && firstItemIndex == 0) {Log.v(TAG, "在move時候記錄下位置");isRecored = true;startY = tempY;}if (state != REFRESHING && isRecored && state != LOADING) {// 保證在設定padding的過程中,當前的位置一直是在head,否則如果當列表超出螢幕的話,當在上推的時候,列表會同時進行滾動// 可以鬆手去重新整理了if (state == RELEASE_To_REFRESH) {setSelection(0);// 往上推了,推到了螢幕足夠掩蓋head的程度,但是還沒有推到全部掩蓋的地步if (((tempY - startY) / RATIO < headContentHeight)&& (tempY - startY) > 0) {state = PULL_To_REFRESH;changeHeaderViewByState();Log.v(TAG, "由鬆開重新整理狀態轉變到下拉重新整理狀態");}// 一下子推到頂了else if (tempY - startY <= 0) {state = DONE;changeHeaderViewByState();Log.v(TAG, "由鬆開重新整理狀態轉變到done狀態");}// 往下拉了,或者還沒有上推到螢幕頂部掩蓋head的地步else {// 不用進行特別的操作,只用更新paddingTop的值就行了}}// 還沒有到達顯示鬆開重新整理的時候,DONE或者是PULL_To_REFRESH狀態if (state == PULL_To_REFRESH) {setSelection(0);// 下拉到可以進入RELEASE_TO_REFRESH的狀態if ((tempY - startY) / RATIO >= headContentHeight) {state = RELEASE_To_REFRESH;isBack = true;changeHeaderViewByState();Log.v(TAG, "由done或者下拉重新整理狀態轉變到鬆開重新整理");}// 上推到頂了else if (tempY - startY <= 0) {state = DONE;changeHeaderViewByState();Log.v(TAG, "由DOne或者下拉重新整理狀態轉變到done狀態");}}// done狀態下if (state == DONE) {if (tempY - startY > 0) {state = PULL_To_REFRESH;changeHeaderViewByState();}}// 更新headView的sizeif (state == PULL_To_REFRESH) {headView.setPadding(0, -1 * headContentHeight+ (tempY - startY) / RATIO, 0, 0);}// 更新headView的paddingTopif (state == RELEASE_To_REFRESH) {headView.setPadding(0, (tempY - startY) / RATIO- headContentHeight, 0, 0);}}break;}}return super.onTouchEvent(event);}/** * 當狀態改變時候,調用該方法,以更新介面 */private void changeHeaderViewByState() {switch (state) {case RELEASE_To_REFRESH:arrowImageView.setVisibility(View.VISIBLE);progressBar.setVisibility(View.GONE);tipsTextview.setVisibility(View.VISIBLE);lastUpdatedTextView.setVisibility(View.VISIBLE);arrowImageView.clearAnimation();arrowImageView.startAnimation(animation);tipsTextview.setText("鬆開重新整理");Log.v(TAG, "目前狀態,鬆開重新整理");break;case PULL_To_REFRESH:progressBar.setVisibility(View.GONE);tipsTextview.setVisibility(View.VISIBLE);lastUpdatedTextView.setVisibility(View.VISIBLE);arrowImageView.clearAnimation();arrowImageView.setVisibility(View.VISIBLE);// 是由RELEASE_To_REFRESH狀態轉變來的if (isBack) {isBack = false;arrowImageView.clearAnimation();arrowImageView.startAnimation(reverseAnimation);tipsTextview.setText("下拉重新整理");} else {tipsTextview.setText("下拉重新整理");}Log.v(TAG, "目前狀態,下拉重新整理");break;case REFRESHING:headView.setPadding(0, 0, 0, 0);progressBar.setVisibility(View.VISIBLE);arrowImageView.clearAnimation();arrowImageView.setVisibility(View.GONE);tipsTextview.setText("正在重新整理...");lastUpdatedTextView.setVisibility(View.VISIBLE);Log.v(TAG, "目前狀態,正在重新整理...");break;case DONE:headView.setPadding(0, -1 * headContentHeight, 0, 0);progressBar.setVisibility(View.GONE);arrowImageView.clearAnimation();arrowImageView.setImageResource(R.drawable.arrow);tipsTextview.setText("下拉重新整理");lastUpdatedTextView.setVisibility(View.VISIBLE);Log.v(TAG, "目前狀態,done");break;}}public void setonRefreshListener(OnRefreshListener refreshListener) {this.refreshListener = refreshListener;isRefreshable = true;}public interface OnRefreshListener {public void onRefresh();}public void onRefreshComplete() {state = DONE;SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");lastUpdatedTextView.setText("最新動向:" + sdf.format(new Date()));changeHeaderViewByState();}private void onRefresh() {if (refreshListener != null) {refreshListener.onRefresh();}}/** * 此方法直接照搬自網路上的一個下拉重新整理的demo,此處是“估計”headView的width以及height * @param child */private void measureView(View child) {ViewGroup.LayoutParams p = child.getLayoutParams();if (p == null) {p = new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,ViewGroup.LayoutParams.WRAP_CONTENT);}int childWidthSpec = ViewGroup.getChildMeasureSpec(0, 0 + 0, p.width);int lpHeight = p.height;int childHeightSpec;if (lpHeight > 0) {childHeightSpec = MeasureSpec.makeMeasureSpec(lpHeight,MeasureSpec.EXACTLY);} else {childHeightSpec = MeasureSpec.makeMeasureSpec(0,MeasureSpec.UNSPECIFIED);}child.measure(childWidthSpec, childHeightSpec);}public void setAdapter(BaseAdapter adapter) {SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");lastUpdatedTextView.setText("最新動向:" + sdf.format(new Date()));super.setAdapter(adapter);}}main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:background="@drawable/bg" android:orientation="vertical" tools:context=".MainActivity" > <com.example.dropdownrefresh.ui.DropdownListView android:id="@+id/listView" android:layout_width="match_parent" android:layout_height="match_parent" android:cacheColorHint="#00000000" android:childDivider="@drawable/list_driver" android:divider="@drawable/list_driver" /></LinearLayout>
下拉頭的布局head.xml
<?xml version="1.0" encoding="utf-8"?><!-- ListView的頭部 --><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="wrap_content" > <!-- 內容 --> <RelativeLayout android:id="@+id/head_contentLayout" android:layout_width="match_parent" android:layout_height="wrap_content" android:paddingLeft="30dp" > <!-- 箭頭映像、進度條 --> <FrameLayout android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentLeft="true" android:layout_centerVertical="true" > <!-- 箭頭 --> <ImageView android:id="@+id/head_arrowImageView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center" android:contentDescription="@null" android:src="@drawable/arrow" /> <!-- 進度條 --> <ProgressBar android:id="@+id/head_progressBar" style="?android:attr/progressBarStyleSmall" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center" android:visibility="gone" /> </FrameLayout> <!-- 提示、最新動向 --> <LinearLayout android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_centerHorizontal="true" android:gravity="center_horizontal" android:orientation="vertical" > <!-- 提示 --> <TextView android:id="@+id/head_tipsTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="下拉重新整理" android:textColor="@color/white" android:textSize="20sp" /> <!-- 最新動向 --> <TextView android:id="@+id/head_lastUpdatedTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="上次更新" android:textColor="@color/gold" android:textSize="12sp" /> </LinearLayout> </RelativeLayout></LinearLayout>
下拉式清單鬆開後需要掃描Wifi,再重新整理列表
package com.example.dropdownrefresh;import java.util.ArrayList;import java.util.HashMap;import java.util.List;import android.app.Activity;import android.net.wifi.ScanResult;import android.os.AsyncTask;import android.os.Bundle;import android.view.View;import android.view.ViewGroup;import android.widget.BaseAdapter;import android.widget.LinearLayout;import android.widget.TextView;import com.example.dropdownrefresh.ui.DropdownListView;import com.example.dropdownrefresh.ui.DropdownListView.OnRefreshListener;import com.example.dropdownrefresh.utils.WifiAdmin;/** * 使用下拉重新整理搜尋wifi * @author Administrator * */public class MainActivity extends Activity {WifiAdmin wifiAdmin = null;private ArrayList<HashMap<String, String>> list;private BaseAdapter adapter;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.main);wifiAdmin = new WifiAdmin(this);list = new ArrayList<HashMap<String, String>>();RefreshList();final DropdownListView listView = (DropdownListView) findViewById(R.id.listView);adapter = new BaseAdapter() {public View getView(int position, View convertView, ViewGroup parent) {LinearLayout layout = new LinearLayout(getApplicationContext());layout.setOrientation(LinearLayout.VERTICAL); //垂直布局HashMap<String, String> map = list.get(position);TextView txtName = new TextView(getApplicationContext());TextView txtSignal = new TextView(getApplicationContext());txtName.setText(map.get("wifi_name"));txtSignal.setText(map.get("wifi_signal"));layout.addView(txtName);layout.addView(txtSignal);return layout;}public long getItemId(int position) {return 0;}public Object getItem(int position) {return null;}public int getCount() {return list.size();}};listView.setAdapter(adapter);listView.setonRefreshListener(new OnRefreshListener() {public void onRefresh() {new AsyncTask<Void, Void, Void>() {protected Void doInBackground(Void... params) {try {Thread.sleep(1000);} catch (Exception e) {e.printStackTrace();}list.clear();RefreshList();return null;}@Overrideprotected void onPostExecute(Void result) {adapter.notifyDataSetChanged();listView.onRefreshComplete();}}.execute(null, null, null);}});}private void RefreshList(){wifiAdmin.startScan(); // 掃描wifi熱點,前提是wifi已經開啟List<ScanResult> wifiList = wifiAdmin.getWifiList();for (int index = 0; index < wifiList.size(); index++) {HashMap<String, String> map = new HashMap<String, String>();map.put("wifi_name", (wifiList.get(index)).SSID);map.put("wifi_signal", "signal: "+ (-(wifiList.get(index)).level) + "%");list.add(map);}}}
相關代碼:http://download.csdn.net/detail/deng0zhaotai/7969215
Android常用控制項之下拉重新整理Wifi列表